ATC Group: S02D Other otologicals

Cinchocaine is a local anaesthetic agent and is suitable for surface or spinal anaesthesia and for relaxing sphincteric spasms. It is an anaesthetic of the amide type. It is more toxic than cocaine by local application but its local anaesthetic action is greater so it can be used in lower concentrations. Its action is more prolonged than lignocaine.

Cocaine is a tropane alkaloid with central nervous systems (CNS) stimulating and local anesthetic activity. Cocaine binds to the dopamine, serotonin, and norepinephrine transport proteins and inhibits the re-uptake of dopamine, serotonin, and norepinephrine into pre-synaptic neurons. This leads to an accumulation of the respective neurotransmitters in the synaptic cleft and may result in increased postsynaptic receptor activation. The mechanism of action through which cocaine exerts its local anesthetic effects is by binding to and blocking the voltage-gated sodium channels in the neuronal cell membrane. By stabilizing neuronal membranes, cocaine inhibits the initiation and conduction of nerve impulses and produces a reversible loss of sensation.

Lidocaine, like other local anaesthetics, causes a reversible blockade of impulse propagation along nerve fibres by preventing the inward movement of sodium ions through the nerve membrane. Local anaesthetics of the amide-type are thought to act within the sodium channels of the nerve membrane.

Phenazone has analgesic and antipyretic properties. Topically, solutions have been used locally as ear drops in disorders such as otitis media because of its local anti-inflammatory and analgesic action.